US2657052A - Sheet delivery mechanism - Google Patents

Description

Oct. 27, 1953 T. J. ELLIOTT SHEET DELIVERY MECHANISM 2 sheets -sheet 1 Filed Oct. 25, 1947 ll/mmmwmum...

Oct. 27, 1953 J, ELLIOTT 2,657,052

SHEET DELIVERY MECHANISM Filed 001;. 25, 1947 2 Sheets-Sheet 2 8%; warm Patented Oct. 27, 1953 SHEET DELIVERY MECHANISM Thomas J. Elliott,

Cleveland, Ohio, assignor to Harris-Seybold Company, corporation of Delaware Cleveland, Ohio, at

Application October 25, 1947, Serial No. 782,152

12 Claims.

This invention relates to improvements in sheet delivery mechanism, and has reference particularly to means for reducing the rate of travel of the sheets after they are released by the conveyor grippers preparatory to being deposited upon the top of the delivery pile.

In sheet handling machines such as printing presses, where the sheets are operated upon individually and then conveyed by gripper conveyor to a delivery point and dropped by the traveling grippers onto a board to form difficulties are experienced when machines are operated at high speed, in that when the sheets are released they strike against the pile guides with such force Furthermore, if the sheets are thin or light in weight they may not drop quickly enough to avoid interference with the succeeding sheet, or they may roll up or fold over on the pile necessitating stoppage of the machine. Thus the speed of operation of the machine is limited by the speed at which the sheets can be dropped and jogged into a satisfactory pile.

Various attempts have been made to improve delivery devices in order to achieve satisfactory Piling at the higher speeds which became available as the design of printing presses improved. One such mechanism comprises a series of rotating suction wheels driven by a mechanical connection with the conveyor at wheel surface speed substantially less than the linear speed of the sheets being drawn over the suction wheels by the conveyor. These wheel have the advantage that they are in continuous rotation, and therefore function to drive the sheet forward at somewhat reduced speed after the sheet has been largely decelerated following release by the grippers. Such devices are subject to the serious disadvantage however that their speed of rotation, and therefore their retarding action upon the sheet, changes when the speed of operation of the machine and its conveyor are changed. That is, as the speed of the conveyor is increased the speed of the suction proportionately. This usually results in an action upon the sheets which is the reverse of What is desired, inasmuch as increased conveyor speed results in increased inertia of the sheets and, to function properly, the suction wheels should exert a greater retarding effect upon the sheets instead of a lesser effect. Thus, when such wheels are properly designed for a given speed of operation of the press they do not function properly at other speeds. Furthermore, sheets of different weights wheels likewise increases,

- different press speeds and different weights and textures of paper stock.

According to the present invention the deficiencies of previous devices are overcome by providing rotating suction wheels for slowing down the sheets and thereafter advancing them onto the pile, which wheels are driven at a selected speed which is independent of conveyor speed and which preferably may be selectively varied by the operator to meet various conditions of conveyor speed and quality of sheets.

One of the objects of the invention therefore is the provision of means for quiet, uniform deposit of sheets dropped from a rapidly moving conveyor.

Another object is the provision of means of the character stated which may be adjusted to compensate for different grades of stock and different printing press speeds.

Still another object is the provision of means for decelerating sheets released by a conveyor, which means shall have motion not directly proportional to the speed of the conveyor, and which shall be adjustable to vary the rate of deceleration for a given conveyor speed.

Other objects and features of novelty will appear as I proceed with the description of that embodiment of the invention which, for the purposes of the present application, I have illustrated in the accompanying drawing, in which Fig. 1, is a side elevational view of a delivery mechanism embodying the invention.

Fig. 2 is an end elevational view partly in section along the line 2-4 of Fig. 1.

Fig. 3 is a detail view, partly in section and on a larger scale, of the jogger and suction wheel mechanism taken along the line 3-3 of Fig. 2.

Fig. 4 is a fragmental detail view, partly in section. of one of the suction wheels.

Fig. 5 is a detail sectional view taken substantially along the line 5-4 of Fig. 1, and

Fig. 6 is a detail elevational view of the mount? ing of one of the jogger plates, taken along the line 6-45 of Fig. 2.

In the drawings the supporting framework of 3 the delivery mechanism is illustrated as comprising frame side members I! and [2 which are joined by tie rods 13 and I4. Sheets are conveyed from the sheet handling machine, such as a printing press, not shown, by an endless conveyor which comprises parallel chains and I5 joined at intervals by gripper bars [1 in the usual manner. The chain l5 runs between tracks [8 on one side of the machine, and the chain I6 runs between tracks I9 on the other side of the machine, which tracks are secured to brackets 23, 2| supported by the frame members ll, [2 respectively.

The conveyor follows an upward path indicated at 22 a it leaves the printing press, the chains passing around idler sprockets 23 rotatably supported on tie rod l3, and then traveling along a horizontal path to the idler sprockets 24; after which the chains return to the printing press along a path not illustrated in the drawings.

Beneath the horizontal run of the conveyor there is a delivery platform 25 upon which the sheets are dropped by the grippers to form a pile 26; the grippers being opened at the proper time to release the sheets by mechanism of known character, such as a crank 3 carried by each gripper bar for normally engaging a cam I fixed in the frame.

The sheets are guided at the front edge of the pile by pile guides 2'! secured to a cross rod 28. The usual stripper fingers 29 are provided for defleeting the sheets downwardly. The platform 25 is lowered in the usual manner as sheets acculnulate in the pile. As the sheets are dropped onto the pile they are jogged into correct lateral alignment by the usual side jogger plates, omitted from the drawings for the sake of simplicity. The sheets are jogged endwise by a mechanism which will now be described.

Pivotally mounted in the frame members I i and I2 is a shaft as which is given a periodic rocking movement in synchronism withthe operation of the press, one complete oscillation for each sheet handled. Secured to this shaft near its ends are two arms 3!, one at each side of the machine. One of these arms is pivotally connected to one end of a slide bar 32, while the other is similarly connectedto a slide bar 33, which bars are there-.

by given a to and fro movement by the oscillation. of shaft 35. The bars 32, 33 are slidably mounted in frame brackets 25, 2! respectively, and held in,

place in those brackets by plates 34.

Supported upon bar 32 is a bracket 35 having a slot therein for accommodating the bar and provided with a plate 36 secured to the bracket by screws 31. Through the plate 36 there extends a thumb screw 38 which bears against the bar 32 for the purpose ofsecuring the bracket 35 in any desired position of adjustment along the bar 32. At the opposite side of the machine bar 33 supports a bracket 33 similar to bracket 35 and provided with a plate 53 and thumb screw 4|, similar in construction and function to the corre' sponding parts of the first described sideof thev machine.

Secured to the top of brackets 35 and 39 there are'further brackets 62 and 43 which support a pipe 45 closed at one end by a cap 45 and provided with a series of small holes 46 from which air under pressureis directed downward for reasons which will appear hereinafter. The open end of pipe 44 is threaded into bracket v42 in communication with a chamber 4'! therein. Into this chamber air under pressure is directed through pipe 48 and flexible hose connection 43 from a source of compressed air, not shown. Another chamber 50 in bracket 42 is connected by pipe 5| and flexible hose connection 52 to a source of suction, not illustrated. Chamber 50 is connected by a short pipe 53 and elbow 54 to a hollow pipe 55 which is rigidly supported in the brackets 35, 39 and is closed at one end by a plug 56.

The brackets 35 and 39 are also joined rigidly by an angle bar 51 which is securedto studs 58 fixed in the brackets 35 and 33. Thus the latter brackets together with the pipe 55 and angle bar 51 form a rigid frame structure adj ustably secured at its ends to bars 32 and 33, and movable back and forth with r the latter bars.

Each of the end jogger plates 53 is carried by means of a pair of gibs 35 upon an upright extension 5! of an arm 62' which is clamped to pipe 55 as illustrated in Fig. 6, which arm is provided with an extension 63 carrying an adjusting screw 64 adapted to bear against angle bar 51. The arrangement is such as to permit accurate vertical alignment of the plates 59 as well as to permit removal or lateral adjustment of the plates.

Secured to the angle bar 5'? is a series of. flexible tapes 65 which extend over idler wheels 66 rotatably mounted on tie rod i3 and downwardly along a line approximately parallel to the path of the conveyor. Weights, not shown, are provided on the ends of the tapes to keep them taut as the angle bar 51 moves back and forth during operation of the machine. The tapes 65 support the sheets as they are drawn along their horizontal path toward the pile.

Adjacent the jogger plates 59 and at points slightly to the rear thereof is a series of suction wheels 65 which are secured to a rotating shaft 6! journaled in the brackets 35 and 39. Midway between the frame members a small bracket 61 embraces shaft 31 and pipe 55 to increase the rigidity of. these members. Referring especially to 'Fig. 4, the wheels 66 are provided in their peripheries with a series of slots 68 which register successively with a hole 59 in the wall of a stationary suction box Til having a chamber 1| formed therein and sealed from the shaft 51 by a bushing' E2. The boxlfl has formed integrally therewith an arm 13 whose bifurcated end straddles pipe 55 and is prevented from movement along the pipe by collars 74. The chamber ll. isconnected by flexible'tubing T5 to suction pipe 55, thereby permitting limited adjustment of the wheel'transversely of the machine. In the operation of the machine suction is induced in the. chamber H and thus in the slots- 63 as they come into position above hole 69.

The rotating shaft 51 is. provided at onev end.

with a bevel gear 76 which meshes with a further bevel gear 1'! which is .slidably keyedto a shaft 18 that is supported in brackets 19 and 8-0 depending from the slide bar 32. j Bracketv 35 is provided.

with a bearing portion 3| through which shaft 18 extends, thereby further supportingthe latter. shaft. Theslidable connection between gear '11- and shaft. 18 is for the purpose ofpreserving the driving connection to shaft 61 while allowing ad.-

' justment of the brackets35- and 39 endwise of. thebars 32 and 33 to accommodate sheets. .of,

different lengths. in any given position of adjust-. ment gear 1landshaft-18 move back and forth in unison withthe brackets 35 and 39 and. their supporting bars. 32 and 33..

Shaft 18 carries near one end a. gear 82 having a narrow. face which is driven by a wide faced gear 83. The latter gear iskeyed to a short shaft 8.4. rotatably mounted in abracket 35 which sur rounds the tie rod l3 and is secured by bolts 86 to the inside surface of frame member I I. Shaft 84 at its other end carries a sprocket 81 which is driven by a chain 88 traveling around a sprocket 89 secured to the output shaft of a variable speed transmission device 90 mounted by bolts 91 on a ledge formed in frame II. The input shaft 92 of the variable speed transmission device carries a spiral gear 92' which is driven by a further spiral gear 93 keyed to a shaft 94 supported in bracket 95 at one end and in frame member l2 at the other end. Shaft 94 is driven at constant speed by an electric motor 95 through belt 91 and pulleys Fill and 99 keyed to the motor shaft and to shaft e4 respectively.

The variable speed transmission device 90 may be of any suitable or desired type. In the illustrated case it has an adjusting crank I which may be manually turned in order to change the speed ratio of the input and output shafts. The speed of the motor 96, the various driving connections and the characteristics of the transmission are so chosen that the speed of the suction Wheels 66 may be varied within the limits required by the speed of the machine and the character of sheets to be delivered It has been found that for a conveyor handling ordinary weights of paper at a maximum speed of about 400 to 500 feet per minute, good results are obtained where the wheel surface speed is adjustable between zero and about 100 feet per minute.

In the operation of the machine sheets are carried by the endless conveyor grippers I! over the tapes 65, the suction wheels 66 and the jogger plates 59 towards the forward end of the pile 26. As the body of a sheet passes over the suction wheels 65 air blasts from the holes 46 in pipe 44 force the sheet down into contact with the suction wheels and suction is applied in the latter wheels so that the sheets are gripped by the latter and are stretched out and held more or less taut as they are drawn over the Wheels by the grippers, the drive for the wheels having been previously adjusted by the operator to provide a surface speed of the wheels somewhat less than the linear speed of the grippers. The adjustment of suction wheel speed is preferably made during operation of the machine and the setting is determined by the nature of the results desired, it being true in general that higher speeds result in depositing the sheets nearer the guides or with greater force against the guides.

Preferably the oscillations of bars 32 and 33 are so timed in relation to the travel of the grippers l I that the jogger plates 59 and their associated suctien wheels 66 are traveling bodily toward the pile 25 at a point about midway of their motion at the time the grippers I1 let go of the forward edge of the sheet. At this moment the tail edge portion of the sheet is still engaged by the suction wheels 56, with the result that the sheet is quickly decelerated to substantially the speed of the suction wheels. Thereafter the continued ro- ,at.ion of the suction wheels permits or promotes further forward motion of the sheet until its rear edge passes the active suction slots at the top of the wheels. At this point the wheels release the sheet. After the wheels and the plates.59 have reached their forwardmost position they withdraw from the pile, permitting the tail portion of the sheet to drop onto the pile in approximately its final position, ready to be jogged into precise alignment by jogger plates 59 upon their next movement toward the pile.

Any desired number of wheels and jogger plates may be employed. Also, suitable adjusting valves will ordinarily be provided to control the extent of air pressure and suction. While I prefer to maintain suction in wheels 66 and pressure in pipe 44 continuously, timing valves may be provided for the purpose of cutting off the suction and pressure during the time the gap between successive sheets on the conveyor is passing the wheels.

Under some conditions it will be possible to omit the variable speed transmission and to drive the suction wheels at a constant speed preselected in accordance with the range of conveyor speeds to be used and the weights, textures and sizes of stock to be run, and such an arrangement is to be considered within the scope of this invention.

By means of the delivery mechanism described above it is possible to achieve the retarding effect desired to meet variations in conditions caused by changes in conveyor speed and in weight and character of stock. In practice it has been found possible to adjust the speed of the suction wheels so that the sheets are deposited on the pile either with slight contact against the guides 21 or at any desired distance from the guides prior to jogging.

Having thus described my invention, I claim:

1. In a sheet delivery mechanism, a sheet conveyor adapted to be driven at different selected speeds and having means for gripping the sheets at their forward ends, suction means adapted to move in the direction of sheet travel over which the sheets are drawn by said gripping means, and manual means adapted to function during operation of the mechanism for controlling the speed of movement of said suction means independently of conveyor speed.

2. In a sheet delivery mechanism, a sheet conveyor adapted to be driven at different selected speeds and having means for gripping the sheets at their forward ends, suction means comprising a suction wheel which is adapted to turn in the direction of sheet travel over which the sheets are drawn by said gripping means, and means for turning said suction wheel at a speed which is unaffected by changes in conveyor speed.

3. In a sheet delivery mechanism, a sheet conveyor adapted to be driven at different selected speeds and having means for gripping the forward ends of the sheets, suction means compris ing a suction wheel which is adapted to turn in the direction of sheet travel over which the sheets are drawn by said gripping means, and manual means adapted to function during op eration of the mechanism for selecting the speed of rotation of said suction means relative to any given conveyor speed.

4. In a sheet delivery mechanism fora variable speed printingpress, a sheet conveyor adapted to be driven at a speed proportional to the speed of the press and having means for gripping the sheets at their forward ends, a rotating suction wheel over which the sheets are drawn by said gripping means, a shaft, means for driving said shaft at a selected speed. unaffected by changes in the speed of the press, and driving connections between said shaft and said suction wheel.

5. In a sheet delivery mechanism for a printing press, a sheet conveyor adapted to be driven at a speed proportional to the speed of the press and having means for gripping the sheets at their forward ends, a rotating suction wheel over which the sheets are drawn by said gripping means, a shaft, means for driving said shaft ata selected speed unaffected by changes iii-the speed of the press,avariable speed trans- 'mission driven by said shaft, and driving condirection of sheet travel at a speed less than that of said grippers, jogger plates for the rear end of said pile, and reciprocating supports for said suction wheel and jogger plates moving forward and backward for each sheet deposited, whereby a sheet may be deposited while said sup ports are in their forward position and the suction wheel and jogger plates then moved backward to permit the rear end of the sheet to settle on the pile.

7. Mechanism as defined in claim 5, characterized by the fact that the top of the pile is maintained below the level of said wheel.

8. In sheet delivery mechanism, a support for a pile of sheets, a sheet conveyor havinggrippers for grasping'the forward ends of sheets,

a continuously rotating suction wheel over which the sheets are drawn by said grippers preparatory; to being deposited upon said pile, the rotation of the upper portion of said wheel being in the general direction of sheet travel at a speed less than that of said grippers, and reciprocating supports for said suction wheel moving forward and backward for each sheet deposited, whereby the slow-down of the bodily travel of the wheel at the forward end of its stroke contributes to the deceleration of the sheet.

9. In sheet delivery mechanism, a support for a pile of sheets, a sheet conveyor having grippers forgrasping the forward ends of the sheets, a continuously rotating suction wheel over which the sheets are drawn by said grippers preparatory to being deposited upon said pile, the rotation of the upper portion of said wheel being inthe general direction of sheet travel at a speed less than that of said grippers, reciprocating supports for said suction wheel moving forward and backward for each sheet deposited, said grippers releasing the sheet while it is traveling over said suction wheel and the slowdown of forward bodily travel of said suction wheel occurring while the sheet is still in engagement with said wheel.

10. In a sheet delivery mechanism, moving conveyor means comprising grippers adapted to convey sheets by their forward ends and to release the sheets at a selected point in their trav-' el, suction means having a sheet contacting surface adapted to move in the direction of sheet travel at a speed less than the speed of said grippers over which the sheets are drawn by said grippers, andmanually adjustable means for varying the speed of movement of at least one of the aforesaid means to establish any one of a plurality of different speed ratios for the conveyor means and suction means, whereby the retarding effect of said suction means upon a sheet released by said grippers may be varied by the operator.

11. In a sheet delivery mechanism, moving conveyor means comprising grippers adapted to convey sheets by their forward ends in a given path and to release the sheets at a'selected point of that path, suction means comprising suction ports in effective relation with the sheet path moving in the direction of sheet travel at a speed less than the speed of said grippers, said suction ports exerting control on the sheets tending to slow down their forward travel, and manually adjustable means for varying the rate of movement of said suction ports independently of the rate of travel of said conveyor, whereby the effect of said suction means upon a sheet released by said grippers may be varied by the operator.

12. In a sheet delivery mechanism, moving conveyor means comprising grippers adapted to convey sheets by their forward ends in a given path and to release the sheets at a selected point in their travel, suction wheels adjacent the path of the sheets and in effective relation therewith, said wheels being movable bodily back and forth adjacent the path of the sheets and being driven to cause their surfaces adjacent said path to rotate in the direction of sheet travel at a speed less than the speed of said conveyor at a time immediately following the release of a sheet by said grippers, and manually adjustable means for varying the speed of rotation of said suction wheels independently of the rate of travel of said conveyor, whereby their retarding effect upon a sheet released by said grippers may be varied by the operator.

THOMAS J. ELLIOTT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,873,316 Droitcour Aug. 23, 1932 2,130,841 Eckhard Sept. 20, 1938 2,208,978 Harrold et al July 23, 1940 2,332,863 Luehrs Oct. 26, 1943 2,381,719 Brintnall Aug. 7,194?) 2,474,997 Wormser July 5,1949

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